Carpenters frequently use a common technique that involves countersinking screws into a work piece (e.g., patio decks), and using a plug to conceal the countersunk screw head. The technique produces a clean and smooth surface, which provides both functional and aesthetic benefits. The plug concealing the screw head is securely retained within the countersunk bore or aperture by a glue or adhesive compound. The plug is inserted into the bore preferably with the top surface flush with the surface of the work piece. The carpenter must ensure that the size and shape of the plug matches the bore. The carpenter must also ensure that only a very small amount of glue is dispensed into the bore to provide good adhesion, while preserving the fit.
Similarly, carpenters also use dowel pins to join two disparate work pieces together. Each of the work pieces includes a bore in which an adhesive is applied therein prior to joining with a dowel pin.
Ideally, the adhesive should be applied to the sides of the bore with very little at the screw head or at the bottom of the bore for dowel pins. In practice, however, the amount of glue applied is imprecise. Conventional nozzles usually dispense in a manner resulting in excessive amounts, which appears at the bottom of the bore. Alternatively, the adhesive may be applied to the plug and inserted into the bore. These methods present several problems, which the present invention is designed to solve.
The holding power of the glue is almost entirely a function of its application on the sidewall of the bore, so that having the glue predominantly residing on the bottom of the bore provides little adhesive strength. Additionally, the pooling of the glue can result in a hydraulic lock effect, which limits the insertion depth of the plug or dowel pin. As a result, the plug is poorly seated within the bore, requiring sanding and cutting to produce a flush, smooth surface. In the alternative, applying glue directly onto the plug is messy and result in excess glue on work surfaces, tools and the like, thus requiring extra clean-up and/or sanding. Accordingly, the process of countersinking screws and plugging the bore and joining work pieces via dowel pins are labor intensive and great care must be taken to produce a functional bond along with a smooth and unmarred surface.
In view of the foregoing problems, there is a need for a nozzle assembly designed to dispense a precise amount of a fluid to a side portion defining a bore or aperture in a work piece, while minimizing undesirable overflows and/or fluid at the bottom of the bore.